CVE-2016-7055 – openssl: Carry propagating bug in Montgomery multiplication

https://notcve.org/view.php?id=CVE-2016-7055

There is a carry propagating bug in the Broadwell-specific Montgomery multiplication procedure in OpenSSL 1.0.2 and 1.1.0 before 1.1.0c that handles input lengths divisible by, but longer than 256 bits. Analysis suggests that attacks against RSA, DSA and DH private keys are impossible. This is because the subroutine in question is not used in operations with the private key itself and an input of the attacker's direct choice. Otherwise the bug can manifest itself as transient authentication and key negotiation failures or reproducible erroneous outcome of public-key operations with specially crafted input. Among EC algorithms only Brainpool P-512 curves are affected and one presumably can attack ECDH key negotiation. • http://www.oracle.com/technetwork/security-advisory/cpujan2018-3236628.html http://www.oracle.com/technetwork/security-advisory/cpujul2017-3236622.html http://www.oracle.com/technetwork/security-advisory/cpuoct2017-3236626.html http://www.securityfocus.com/bid/94242 http://www.securitytracker.com/id/1037261 https://access.redhat.com/errata/RHSA-2018:2185 https://access.redhat.com/errata/RHSA-2018:2186 https://access.redhat.com/errata/RHSA-2018:2187 https://h20566.www2.hpe.com/hpsc/doc/public • CWE-682: Incorrect Calculation •